930 Porsche 911 'Flachbau' Is Gorgeous Low Mile Gem, Headed to Auction

Rare Porsche 930 Turbo Cabriolet Set for Auction

A pristine 1989 Porsche 911 930 Turbo Cabriolet, finished in the striking Guards Red with a black leather interior, will be auctioned by Bonhams Cars on October 4. This particular model stands out with its rare M505 Slantnose, or “Flachbau,” bodywork, a motorsport-inspired design that makes it one of the most sought-after 911s ever produced. With only 9,828 miles on the clock, it is a rare survivor, preserved in near-original condition—a true treasure for collectors who appreciate both performance and pedigree.

The Iconic Flachbau Design

The Flachbau body style, introduced as an official Porsche option in 1986, dramatically altered the look and aerodynamics of the 911. The front end, inspired by Porsche’s legendary 935 race car, replaced the traditional rounded headlights with pop-up lamps and added unique steel fenders with cooling vents. The car also features aggressive side skirts and rear wheel flares, which further enhance its track-ready stance. The 930 Turbo Cabriolet combines these distinctive design cues with a 3.3-liter turbocharged engine, delivering 282 horsepower at 5,500 RPM, and a top speed of 160 mph—an astonishing figure for its time.

Impeccably Maintained Over Decades

What sets this Porsche apart isn’t just its rarity or performance—it’s the exceptional care it has received throughout its life. This 930 Turbo Cabriolet has had only two owners, with the past 16 years under the meticulous stewardship of a dedicated Porsche enthusiast. 

Factory Fresh

Stored in a climate-controlled garage, the car remains in remarkable condition, with all original factory labels, decals, and date-coded components intact. Even the convertible top has been regularly maintained and exercised, ensuring it operates as smoothly as when it left the factory—a level of care seldom seen in cars of this vintage.

Originality and Provenance

Collectors prize originality, and this Porsche delivers. It retains its factory-installed engine and the desirable G50 five-speed manual transmission, a detail verified by the Porsche Production Specifications certificate. Delivered new in Monaco, the car is believed to have been owned by a member of the Monegasque Royal Family, adding an air of prestige to its history—though this claim remains unverified. Its nearly untouched 9,828 miles and complete set of factory accessories, including the original tool roll, air pump, owner’s manual, and stamped service booklet, make it an authentic and well-documented example.

A Collector’s Dream

As classic Porsches from the 1980s become increasingly collectible, this 1989 Porsche 911 930 Turbo Cabriolet stands out as an extraordinary opportunity. Its combination of rarity, condition, and provenance is sure to attract discerning collectors when it crosses the auction block. Whether it’s the pristine Guards Red paint, the matching-numbers drivetrain, or the coveted M505 Slant Nose configuration, this Porsche represents the ultimate expression of 1980s automotive engineering. Bonhams Cars’ upcoming auction could offer one fortunate buyer the chance to own one of the finest-preserved examples of this iconic model.

Headed to Auction

Part of the Audrain Concours Auction, which will be held by Bonhams on October 4th, this beauty will surely turn heads in Newport, RI. The estimates show the Slantnose 930's value to be between $350,000 and $425,000. We will keep an eye on the results to see how much the car ultimately fetches when it crosses the block.

>>Join the conversation about this 930 Turbo Flachbau right here at Rennlist.com.

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